Improvement in compositions for artificial leather



UNITED STATES PATENT OFFICE.

IMPROVEMENT IN COMPOSITIONS FOR ARTIFICIAL LEATHER.

Specification forming part of Letters Patent No. 20,383, dated May 25,1358.

To ctZZ whom it may concern.-

Be it known that I, SAMUEL WHITMARsH, of Northampton, in the county of.Hampshire and State of Massachusetts, have invented a new and usefulfabric intended as a substitute for leather and for other usefulpurposes; and I do hereby declare that the following is a full, clear,and exact description of the same.

The fabric which constitutes my invention is composed of cotton or otherfibrous substance, either woven into cloth or in an unwoven state,saturated and coated with a compound of linseed-oil and burnt umber,prepared by boiling in every gallon of oil about three pounds of umberin a powdered state for such a length of time that the composition, whencool,wi1l roll in the hands without sticking. This fabric may be made informs suitable for the soles of boots and shoes, coverings for trunks,traveling-bags, caps, cap-fronts, or as a substitute for carriage andharness leather, or for hose-pipe or machine-belting. The mode ofproducing the fabric differs to some extent, according to its form orthe purpose for which it is intended; but the elements thereof are inall cases the same.

To prepare the compound for saturating and coating the fibroussubstances, I put the oil into a suitable vessel having afire under it,or heated by other suitable means, and as soon as it boils add the burntumber, stirring it while the latter is introduced, and also stirring itconstantly or frequently during the subsequent boiling, to cause aperfect mixture of the umber and oil and prevent the burning of the oil.The boiling of the mixture shouldbe continued as gently as possible forfrom twelve (12) to twenty-four (24:) hours, the time varying accordingto the state of the weather or quality of the oil. The boiling will havebeen sufficient when a few drops taken out and cooled will roll betweenthe hands or the finger and thumb without feeling in the least degreesticky. When it has arrived at this state, it may be applied at once tothe fibrous substances, but it may be allowed to cool and be remelted byheat, as required for use.

To make the fabric in a suitable form for coverings of trunks,traveling-bags, caps, capfronts, or as a substitute for carriage orharness leather, I take a single sheet or piece of cotton or other clothand spread thesame up on a hollow iron table or slab heated by steam,

and having the compound of oil and umber, prepared as before described,athand, I with a trowel or other suitable implement spread it all overthe sheet or piece, first on one side and then on the other, and by theheat of the table or slab the cloth will be caused to absorb a greatportion of the compound. I leave enough of the compound on the twosurfaces of the cloth to cover it well and fill up as much as possibleall the small cavities between the threads, and afterward, while it isstill on the table, I pass over it a heavy metal roller, or else removeit from the table and pass it between a pair of metal pressure-rollersto press it as smooth as possible. The fabric thus produced onlyrequires to be exposed in a dryingroom to a heat of from 100 to 130Fahrenheit for about twenty-four h ours, for the purpose of curing it,torender it fit for use. It may then be enameled in the same way asleather, if desired.

Instead of using woven cloth, as before described, the fabric may bemade for some of the above purposes where great tenacity is not so muchan obj eet as a close texture and smooth surface-as, for instance, forcovering trunks or other articlesby saturating a sheet ofcotton-batting. To apply the compound to a sheet of cotton-batting, asufficient quantity of it should be spread on one side of apiece ofcotton or other cloth. The batting should be then laid on the steamtable or slab before mentioned and the piece of cloth placed on the topof it, with the compound next the batting, and a heavy metal rollerpassed over it, whose pressure and the heat of the table or slab willcause the batting to absorb the compound, after which the cloth may beeasily stripped off. The same operation may be and sometimes willrequire to be repeated on the opposite side of the sheet of batting. Thesaturated sheet is then pressed between a pair of metal pressure rollersto compress it and give it a close text-.

ure. The fabric thus produced requires to be dried or cured in the sameway as that made in the manner first described, and it may b afterwardenameled.

- To make a substitute for sole-leather or other stout leather, two ormore sheets of batting may be laid together and treated as above de*scribed, or may have the compound applied to them separately, in themanner above described, and be afterward combined by pressing themtogether by the roller on the steamtable or between pressure-rollers.

To make hose-pipe, I take a woven tube or a pipe made-by folding a pieceof cotton or other cloth and sewing the edges together, and fill thesaid tube with the melted or still fluid compound, and while one end ofthe tube or pipe is closed I apply a pressure to the compound within bymeans of a force-pump or other apparatus to force the compound into andamong the threads and fibers, to saturate the same as far as possible,and afterward coat the outside of the tube with the melted compound,either by passing it through the compound in a suitable vessel or byapplying the compound with a brush or other suitable implement to theexterior. I afterward lay the pipe upon the steam table and pass theroller over it, to cause the superfluous compound to be expressed fromthe interior, and after opening the pipe by forcing water through it assoon as the outside is dry enough to handle viz., about two days-I hangit to cure in a dry apartment about three or four days, after which itis fit for use.

Tomake machine-belting, I employ several thicknesses or plies of strongcotton cloth or canvas, which I saturate, coat, and cement toand run aseam along the outer edge of the piece through the whole of the plies byasewing-machine. I afterward fill every one of the spaces between theseveral plies with the melted or still fluid compound of umber and oilin the same manner as above directed for preparing the hose-pipe, andthen lay the belt upon the steam-table, and after coating the exteriorwith the compound I pass the pressure-roller over it to force out allthe superfluous compound and cause the cementing together of the severalplies, after which it is to be cured by being hung for a few days in adry apartment. WVhen the exterior coating of the belt is hard, it issufficiently cured. The compound in the interior, being unexposed to theatmosphere, will remain soft, and thus cause the belt to have therequisite flexibility, while the exterior surface is very hard and toughand capable of wearing for a very long time.

The fabric prepared in any of the ways hereinbefore described may beused for steam or other packing.

I do not claim, broadly, the saturation of ing umber or othersubstances; but

What I claim as my invention, and desire to secure by Letters Patent, is

The fabric within specified, composed of cotton or other fibroussubstance in a woven or unwoven condition, saturated-or coated with acompound of linseed-oil and burnt umber that has been prepared as hereindescribed.

SAMUEL WHITMARSH.

Witnesses W. F. PRATT,

A. W. THAYER.

cloth and other fabrics in linseed-oil contain-

